Ball joint



FIG. 1 is a front elevational view of a ball joint showing our new design.

FIG. 2 is a rear elevational view thereof.

FIG. 3 is a right side elevational view thereof.

FIG. 4 is a left side elevational view thereof.

FIG. 5 is a top plan view thereof.

FIG. 6 is a bottom plan view thereof.

FIG. 7 is a front, top, and right side perspective view thereof; and,

FIG. 8 is a rear, top, and left side perspective view thereof. 

CLAIM The ornamental design for a ball joint, as shown and described. 